Measurement of safe thermal therapy levels: the case of ultrasonic waveguide interstitial applicator array

This paper addresses the issue of heat toxicity using as an example heating with ultrasonic interstitial waveguide four-applicator array. We show that the experimental heating curves are closely followed by the ones from our FEA modeling using realistically shaped model. The thermal dose was calculated at locations considered to be at the border of the safe dose and compared to 20 CEM₄₃ considered in literature as the safety threshold. We found some discrepancy between the two on comparison. In the paper, we propose an approach that leads to compromise between them; at the same time it helps to define the threshold temperature for each case